The gallbladder is an organ that stores bile, which is a fluid involved with digestion. Sometimes, substances in the bile can harden to form gallstones. Most people with gallstones do not have any symptoms. Some patients can develop symptoms from gallstones, which include abdominal pain, nausea, and vomiting. Gallstones can also lead to other complications such as inflammation of the gallbladder (cholecystitis), pancreas (pancreatitis), or infection of the bile ducts (cholangitis).